title: Vitamin supply in pregnancy for prevention of congenital birth defects.
abstract: OBJECTIVE
  After the short summary of history of primary prevention of neural tube defects by folic acid or folic acid-containing multivitamin supplementation during the periconception period, the three main unsolved problems are highlighted.
  
  
  RESULTS
  Both intervention trials and observational studies confirmed that this new primary preventive method is effective - beyond the prevention of neural-tube defects - in the reduction of the most common structural birth defects: congenital cardiovascular abnormalities. Nevertheless, this important progress in the field of congenital abnormalities is not appreciated appropriately. The periconception supplementation of both folic acid alone and folic acid-containing multivitamin is useful; however, the available data indicate the higher efficacy of multivitamins in the primary prevention of neural-tube defects and congenital cardiovascular abnormalities. The optimal dose of folic acid is not known though this knowledge would be necessary from both a scientific and practical aspect.
  
  
  CONCLUSIONS
  Periconception folic acid or folic acid-containing multivitamin supplementation has resulted in a breakthrough in the primary prevention of neural-tube defects, cardiovascular abnormalities and probably some other defects; however, extra efforts are necessary to eliminate folic acid or folic acid-containing multivitamin preventable congenital abnormalities.
authors.affiliation: Foundation for the Community Control of Hereditary Diseases, Semmelweis University, School of Medicine, Budapest, Hungary. czeizel@interware.hu
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Czeizel
authors.forename: Ferenc
authors.initials: F
authors.lastname: Bánhidy
mesh_terms: D018376:Cardiovascular Abnormalities / Q000517:prevention & control*; D019587:Dietary Supplements; D005260:Female; D005492:Folic Acid / Q000627:therapeutic use*; D006801:Humans; D009436:Neural Tube Defects / Q000517:prevention & control*; D011247:Pregnancy; D011295:Prenatal Care; D011322:Primary Prevention; D014815:Vitamins / Q000627:therapeutic use*
chemical_list: D014815:Vitamins; D005492:Folic Acid